The principal objective of this program is to study the central nervous system electrical correlates of wakefulness and sleep and the interrelationship of CNS mechanisms for sleep and those of internal inhibition. Six projects are currently underway: (1) Forebrain-ponto-mensencephalic-medullary state dependent modulation of reflexes during wakefulness and sleep; (2) Single unit activity during wakefulness and sleep: studies in the brain stem; (3) The PGO spike of the abducens nucleus in comparison to the PGO spike of the lateral geniculate nucleus; (4) The electromyography of tongue muscles during sleep; (5) State pattern development in kittens; (6) On-demand electrical stimulation of the mesencephalic reticular formation to maintain wakefulness.